Countersinker or the like for nuts



Aug. 15,1944. K, o u 2,356,087

COUNTERSINKER OR THE LIKE FOR NUTS Filed March 25, 1943 v 3 Sheets-Sheet1 ATTORNEY Aug. 15, 11944.

PROKUL 2,356,087

COUNTERSINKER OR THE LIKE FOR NUTS Filed March 23 1943 3 Sheets-Sheet 2INVENTORI ATTORNEY Aug. 15, 1944. M. K. PROKUL COUNTERSINKER OR THE LIKEFOR NUTS Fil ed March 23, 1943 3 Sheets-Sheet 3 76 64 76 I Il ATTORNEYPatented Aug. 15,1944

COUNTERSINKER OR THE LIKE FOR NUTS Michael K. Prokul, Maplewood, N. Jassignor to Elastic Stop Nut Corporation of America, a corporation ofNew Jersey Application March 23, 1943, Serial No. 180,167

(C1. Ill-'75) Claims.

This invention relates to apparatus for performing a tool operation on aplurality of similar articles, such as a countersinker or tapper fornuts, and is of particular importance in connectio with asymmetricalarticles, such as the type of nut disclosed in U. S. Patent No.1,550,282. In this type of nut, a locking insert or washer, preferablyformed of fiber or the like, is heldat one end of the threads in awasher well, the sides of the well being crimped over. onto the washer.

When a bolt or screw is threaded intosuch a nut,,the bolt makes its ownthreads in the washer and, as generally recognized, the washer forcesthe. load side of the bolt threads against the load side of the nutthreads at all times, so that the friction between the load sides of thethreads will USS hex nut, is countersunk at bothends, and

machines exist for simultaneously ccuntersinking both ends of the boreof such symmetrical nuts. However, it is diiiicult to adapt suchmachines to operate efliciently and efiectively in countersinkingasymmetrical nuts, only one end of which is to be countersunk.

- Among the objects of this invention are to provide an improvedapparatus-such as a countersinker, tapper, or the like-for performingatool operation on a plurality of similar articles; to provide suchapparatus which will be substantially automatic in operation; to providesuch apparatus in which the articles may be fed in succession to apredetermined position, and held securely in such position while thetool operation is being performed; to provide such apparatus in whichthe next'arti'cle will automatically replace the preceding article afterthe operation has been performed; to provide suchapparatus which iscapable of being easily altered to perform other operations, merely bychanging the tool; to provide apparatus for performing a rotary tooloperation on a plurality of similar articles; and to provide apparatusof the foregoing character which is light in weight, relatively simplein constructiomemclent in operation, and particularly adapted, toperform a tool operation on a plurality of similar asymmetricalarticles.

Other objects and novel features of this invention will become apparentfrom the following description and accompanying drawings, in which Fig.1 is a perspective view illustrating-one form of apparatus constructedin accordance with this invention, comprising a nut counter sinker; I i

Fig. 2 is a plan view of an operating base or table unit of theapparatus of Fig.

Fig. 3 is a plan view of a portion of the operating table, with themoving parts in a position dilferent from that of Fig. 2;

Fig. 4 is a plan view of a portion of the operating table unit, similarto Fig. 3, but illustrating a still difierent position of the movingparts;

Fig. 5 is a vertical section taken through the table alongline 5-5 ofFig. 2;

Fig. 6 is a cross-section of the table taken along line 6-6 of Fig. 2;

Fig. 7 is a perspective view of a section of the table of a modifiedform of apparatus, also constructed in accordancewith this invention;

Fig. 8 is a cross-section of the table taken along line 8-8 of Fig. 7;and v Fig. 9 is a plan view on an enlarged scale, and partly in section,of the end portion of the table of the apparatus of Fig. '7.

One form of apparatus-constructed in accordance with this invention,comprising a nut countersinker as shown in Fig. 1, includes a feed chuteF for leading nuts N to a pair of jaws J1 and Jr. The jaws convey eachnut, in turn, to a predetermined position at which an operation is to beperformed thereon by a tool T. In the pres- ,out pin K andsimultaneously move apart, so that be found unnecessary, directs a jetof compressed air against the nut while his being countersunk, to blowaway chips that might lodg between and interfere with the operation ofany of the moving parts. Jaws J and J: hold-the nut in the desiredposition during countersinking, then move the nut to a position beneathaknock4 the nut may drop'into a chute to be carried to a bin or othersuitable receptacle beneaththe apparatus. Jaws J1 and J: slide in agroove II formed in a block ll, which is mounted on a platform IS, inturn supported by a standard ll 7 move upwardly and downwardly. Abracket 21,

attached to the end of bar 23 opposite cam follower 2|, carries anadjustable set screw 28 adapted to engage a lever pivotally connectedat'its lower end to block I4 and at its upper end to a rod 30. Rod illis pivotally attached to the crank arm of lever l2. Forward movement ofbar 23 rotateslever 12 in a counterclockwise direction, pulling chuck lldown against spring pressure, exerted inside head H, while rearwardmrggment of bar 22 permits the chuck to rise as As in Figs. 2 and 3,chute F includes a channel or trough II and a pair of cover plates 22,which leaves sufllcient room therebetween for inserting a small tool orthe like to move, nuts upwardly or downwardly therein. The nuts may besupplied to chute F from a selective hopper or feed device, whichinsures that the nuts will be fed in orderly arrangement down the chute.The chute is placed at a suflicient angle to the horizontal so that thenuts-will slide easily. and be automatically fed by gravity-acting boththrough the weight of each nut and through the pressure of nuts furtherup the chute -to the laws or other desired position.

As in Figs. 2-6, Jaws J1 and J: are complementary. Jaw J1 being providedwith a ton ue 32 having a 120 fork 34 and Jaw Jr witha cooperating 120"fork 35. As in Fig. 2, these forks and the side of jaw J: along whichtongue 2; slides, form five of the six sides, of a hexagon, thus holdinga hexagonal nut firmlyv and securely. The lower end of the chuteterminates at a point a slight distance laterally from the center lineofdrlll I 0, so, that when the jaws arevopen and in position to receivethe nut, the nut will clear the extending point of the fork of jaw Jr.The laws tend to be held open by a compression spring 36, but can openonly a predetermined limited amount, being restrained by a detent pin 31attached to law J2 and moving within the limits of a slot 38 in the sideof jaw J1. Jaw J1 tends to be pulled to the left by a tension spring 39,while'a stop 40 in law guide groove l3 limits movement of jaw J: to theright.

Assuming that cams l9 and 20 are in the position shown in Fig. 2, withthe drill chuck descending during a counterboring operation, the nutwill be held securelyin position, since cam 20 will have forced follower22 to the right and, with it, both jaws. With the cams rotating in thedirection of-the arrow of Fig. 2', and moving toward the Fig. 3 and thenthe Fig. 4 positions, as indicated on Fig. 2, the highest point of cam19 will shortly pass the follower 2|.

At this time, the nut will have been countersunk to a predetermineddepth, determined by the highest point of cam l9 and the adjustment ofset screw 28, and the chuck will begin to come back up. Shortlythereafter, due to the configuration of cam 20, cam follower 22 and lawcausing the nut to drop freely through a hole 41 in block l4 into anoutlet chute 41, as in Figs. 5 and 6. The lower end of th knockout pinis slightly below the top of the nut as it comes beneath the pin, and,as in Fig. 5. the coil spring 46 is compressed by the nut as it iscarried along by law Jr, the pressure of the spring snapping the nutdown into the chute.

Holder 4! is mounted on a bracket II, attached to block l4 atop a plateII, which forms a cover for sliding bar 23. As in Figs. 1, 2, and 5,plates 52 and 52 similarly provide covers for sliding jaws J1 and J2.

Chuck II and cam shaft 18 are rotated at suitable speeds by conventionalmotor and gear reduction drives-or in any other suitable man net. Thespeed of the chuck and cam shaft is, and configuration of cams I! and20, are so chosen that upward and downward movements of the chuck arecorrelated with the reciprocal movements of the jaws, and with theoptimum drilling speed, so that the drill begins to come down as theiaws begin to close on a nut and the laws begin to move back as thedrill begins to move up. Of course, there is normally provided a'slighttime lag between the start of the upward movement of the drill and theleftward movement of the laws, since the drill must disengage itself [mmthe hole it has countersunk. However, the distance that the. drill musttravel and the distance that the laws must travel is relatively small,and the laws and adjacent portionsv of the apparatus are preferably soconstructed that they do not interfere with the free movement of thedrill. In addition, cam ll is preferably so constructed that drill I0 ispermitted to come back up much faster than it went down. I a

In the modification illustrated in Figs. '1 to 9, inclusive. the nutsare fed down a chute F as before, but are received in a passage flankedby guideways mounted in a block I9. The passage is substantiallyperpendicular to the movement of the nuts in chute F, and a plunger Phaving a tongue Bl extending into the passage between guideways ID,pushes each nut along the passage in succession. The nd of tongue BI isforked as at 62 so as more readily to catch the hex. If the nut is notstraightened by fork r 62, it will be straightened by a pair of blocksII,

the ends of which are provided with vertical grooves 64 which will catchthe corner of the hex and cause the nut to twist around in the passageuntil two sides of the hex are parallel with two sides of the passage.Blocks 6! are pressed against the nuts by springs ll, extending intosuitable drillings in the blocks, as in Fig. 8.

J1 will follow the cam back to the left, tension spring 39 pulling them.As jaw J1 moves to the left, compression spring 36 holds law J: againststop 21 and causes the laws to separate, until pin 31 engages the leftend of slot 38, as in Fig. 3; when the jaws will begin to move to theleft in unison,- thus pulling the nut along and into discharge positionunder knockout pin K, asin Fig. 4.

Knockout pin K is mounted in a holder 45 and is surrounded by a coilspring 48 so that resilient pressure will be exerted on the nut,

The passage formed by guideways O0 is narrower at the discharge end thanat the inlet end, in order to permit easy entrance but toprevent'possibility or misalignment for the countersinking operation.Cover plates 06 of Fig. 8, which .are attached to the guideways byscrews in tapped holes 61 and are accurately positioned by templateholes fitting over pins ll of Fig. 7, prevent the nuts from jumping outof the passageway, and are spaced slightly apart. The distance betweenplates 66 is Just suilicient so that the drill or other tool may comedown between the plates.

To hold each nut securely in longitudinal position during the drillingor other operation, four detent pins' ll are provided. Each detent pin,as in Fig. 9, is provided with a front hemispherical end H and a rearcylindrical end 12, with a cylindrical shoulder between. Thehemispherical ends of the pins stick out through suitable'hoies 14 inthe guideways, while the nuts in position, as in Fig. 9. As a nut ispushed into operating position, in passing it depresses the two reardetent pins, and then slips past into \a position between the front andrear detent pins, the rear detent pins springing back into place. "Eachnut is thus held securely in correct positicTn beneath the tool. Afterthe countersinking operation or the like *has been completed, the lineof nuts in the passage is pushed along by the plunger, and the lastnutthe nut which has just been countersunk-is moved on past the frontpair of detent pins, depressing them. When the rear inclined surfaces ofthe hex reach the curved surfaces of the pins, the nut is ejected fromthe passage with a snapping action. With suitable spring pressure behindthe detent pins, the nuts can be given sufllcient impetus to travelseveral feet upon being ejected, and it is desirable to provide somesort of collecting trough adjacent the point of ejection, the troughleading to a chute or suitable receptacle for catching the nuts. An airsupply for blowing away chips, preferably in a direction transverse tothe passage between guideways 00, may be added, if desired.

Reciprocation of plunger P of Fig. 'l is correlated with the reciprocalmotion of bar 23 in any suitable manner, as by cams, as in the previousmodification. Or, plunger P and bar 23 may be actuated by electricallycontrolled and timed air operated pistons, so that the drill will be into come down while the next nut is still being pushed into position, andthe next nut will begin to be pushed into position while the drill isstill going up from the previous nut. As apparatus constructed inaccordance with this invention has been proven capable ofcountersinking-as many as 250 nuts per minute. proper timing isimportant for emcient and effective operation. 7

Although this invention has been described with reference to apparatusfor countersinking nuts or the like, it will be understood that theprinciples thereof are applicable to the construction of many differenttypes of machines.,

a machine without necessarily utilizing the remaining features. It willbe further'understood that other changesmay be made without departingfrorfi the spirit and scope of this invention,

as defined in the appended claims.

What is claimed is:

1. Apparatus for performing acountersinking I or the like operation on aplurality of hexagonal,

articles such as nuts, comprising a, feed. chute; a pair of lawsdisposed adjacent the lower end of said chute and along a path extendingat an angle to the lower end of said feed chute, .said

jaws having cooperating complementary forks adapted to close uponopposite sides of a hexagonal article to clamp said article; and meansfor moving said Jaws in a direction away from the lower end of said feedchute and simultaneouly closing said jaws, and also returning said jawsin a direction toward said chute and simultaneously causing said jaws toseparate, whereby said jaws are adapted to move an article from saidfeed chute to a predetermined pomtion, clamp said article securely insaid position while a tool operation is performed thereon, move saidarticle away from said position and release the same, and then receiveanother article from said chute.

2. Apparatus as d'eflnedin claim 1, including a resiliently mountedknockout pin for pushing an article from said jaws while separated.

3. Apparatus as defined in claim 1, including a resiliently mountedknockout pin disposed on.

5. Apparatus of the character described, comprising a feed chute for aplurality of articles;

a reciprocating plunger for moving said articles, in succession, fromthe lower end of said feed chute along a'patndispos'ed at an angle tosaid chute; a guide on each side of said path; and means disposed at apredetermined position along said guide to hold each article insuccession in position for a tool operation to be performed thereon,which saidholding means comprises a plurality of pins having roundedends extending through apertures in said guides, and shoulders againstwhich resilient means press to urge said pins inwardly toward saidarticles, said pins being disposed so that at least one pin is in frontof and one behind an article when in said tool operation position.

MICHAEL x. PROKUL.

